b21dcbcaa1
I wasn't entirely sure whether this should return a value or a pointer to
satisfy the interface. Both works, so I benchmarked it elsewhere (REST
mapper). Mem allocs are the same (one alloc/call), but returning a value is 10%
slower when calling one method.
What I then benchmarked is whether pointer vs value receiver in the wrapper
makes a difference. Converting from value receiver (what I had before) to
pointer receiver reduced call overhead by 6%. That's because with a value
receiver, Go has to auto-generate a variant with pointer receiver and calls the
value receiver through that.
That can be seen in a debugger (call stack) and when setting breakpoints:
(dlv) b restMapperWrapper.KindForWithContext
Command failed: Location "restMapperWrapper.KindForWithContext" ambiguous: k8s.io/apimachinery/pkg/api/meta.restMapperWrapper.KindForWithContext, k8s.io/apimachinery/pkg/api/meta.(*restMapperWrapper).KindForWithContext…
Conventional wisdom is to define types with value receiver because those can be
called also on unmutable instances, making them more flexible.
But for types which will only ever be used via a pointer, I think pointer
receiver is better for the reasons above (small performance difference, easier
to debug).
External Repository Staging Area
This directory is the staging area for packages that have been split to their own repository. The content here will be periodically published to respective top-level k8s.io repositories.
Repositories currently staged here:
k8s.io/apik8s.io/apiextensions-apiserverk8s.io/apimachineryk8s.io/apiserverk8s.io/cli-runtimek8s.io/client-gok8s.io/cloud-providerk8s.io/cluster-bootstrapk8s.io/code-generatork8s.io/component-basek8s.io/component-helpersk8s.io/controller-managerk8s.io/cri-apik8s.io/cri-clientk8s.io/csi-translation-libk8s.io/dynamic-resource-allocationk8s.io/endpointslicek8s.io/externaljwtk8s.io/kmsk8s.io/kube-aggregatork8s.io/kube-controller-managerk8s.io/kube-proxyk8s.io/kube-schedulerk8s.io/kubectlk8s.io/kubeletk8s.io/metricsk8s.io/mount-utilsk8s.io/pod-security-admissionk8s.io/sample-apiserverk8s.io/sample-cli-plugink8s.io/sample-controller
The code in the staging/ directory is authoritative, i.e. the only copy of the code. You can directly modify such code.
Using staged repositories from Kubernetes code
Kubernetes code uses the repositories in this directory via a Go workspace and
module replace statements. For example, when Kubernetes code imports a
package from the k8s.io/client-go repository, that import is resolved to
staging/src/k8s.io/client-go relative to the project root:
// pkg/example/some_code.go
package example
import (
"k8s.io/client-go/dynamic" // resolves to staging/src/k8s.io/client-go/dynamic
)
Creating a new repository in staging
Adding the staging repository in kubernetes/kubernetes:
-
Send an email to the SIG Architecture mailing list and the mailing list of the SIG which would own the repo requesting approval for creating the staging repository.
-
Once approval has been granted, create the new staging repository.
-
Update
import-restrictions.yamlto add the list of other staging repos that this new repo can import. -
Add all mandatory template files to the staging repo as mentioned in https://github.com/kubernetes/kubernetes-template-project.
-
Make sure that the
.github/PULL_REQUEST_TEMPLATE.mdandCONTRIBUTING.mdfiles mention that PRs are not directly accepted to the repo. -
Ensure that
docs.gofile is added. Refer to #kubernetes/kubernetes#91354 for reference. -
NOTE: Do not edit go.mod or go.sum in the new repo (staging/src/k8s.io//) manually. Run the following instead:
./hack/update-vendor.sh
Creating the published repository
-
Create an issue in the
kubernetes/orgrepo to request creation of the respective published repository in the Kubernetes org. The published repository must have an initial empty commit. It also needs specific access rules and branch settings. See #kubernetes/org#58 for an example. -
Setup branch protection and enable access to the
stage-botsteam by adding the repo inprow/config.yaml. See #kubernetes/test-infra#9292 for an example. -
Once the repository has been created in the Kubernetes org, update the publishing-bot to publish the staging repository by updating:
-
rules.yaml: Make sure that the list of dependencies reflects the staging repos in theGodeps.jsonfile. -
repos.sh: Add the staging repo in the list of repos to be published.
-
-
Add the staging and published repositories as a subproject for the SIG that owns the repos in
sigs.yaml. -
Add the repo to the list of staging repos in this
README.mdfile.